New on Archive.org, from 1955, The Lovecraft Collectors Library, Volume V: The Amateur Journalist and The Lovecraft Collectors Library, Volume VII: Bibliographies, both now superseded but possibly of interest for those without Joshi’s Bibliography and the Collected Essays.

But The Lovecraft Collectors Library, Volume VI: Commentaries places online short works previously been available in the now expensive print volume Lovecraft Remembered…

Idiosyncrasies Of H.P.L., by E. A. Edkins.
A Few Memories, by James F. Morton.
Ave Atque Vale!, by Edward H. Cole.
The Cthulhu Mythos: A Study, by George T. Wetzel.
The Lord Of R’lyeh, by Matthew H. Onderdonk.